Ammonia is one of the most widely produced chemicals in the United States. In pure form, it is known as anhydrous ammonia. Ammonia is also produced in the human body and is commonly found in nature. It is essential in the body as a building block for making proteins and other complex molecules. In nature, ammonia occurs in soil from bacterial processes. It is also produced when plants, animals and animal wastes decay.
View a FREE sample. The area in which water enters an aquifer. In a recharge zone surface water or precipitation percolate through relatively porous, unconsolidated, or fractured materials, such as sand, moraine deposits, or cracked basalt, that lie over a water bearing, or aquifer, formation.
1 the zone between the ground surface and the water table where pore spaces of the rock or soil may be partly filled with air and partly with water is referred to as the unsaturated zone or vadose zone and water in this zone is referred to as soil moisture (Fig). recharge is the water entering the saturated zone. 2  in many parts of the world, groundwater is the only source of fresh water. 3  in the US about 10% of the rainfall becomes groundwater eventually.